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/* @(#)w_exp.c 5.1 93/09/24 */
/*
* ====================================================
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
*
* Developed at SunPro, a Sun Microsystems, Inc. business.
* Permission to use, copy, modify, and distribute this
* software is freely granted, provided that this notice
* is preserved.
* ====================================================
*/
#ifndef lint
static char rcsid[] = "$Id$";
#endif
/*
* wrapper exp(x)
*/
#include "math.h"
#include "math_private.h"
#ifdef __STDC__
static const double
#else
static double
#endif
o_threshold= 7.09782712893383973096e+02, /* 0x40862E42, 0xFEFA39EF */
u_threshold= -7.45133219101941108420e+02; /* 0xc0874910, 0xD52D3051 */
#ifdef __STDC__
double exp(double x) /* wrapper exp */
#else
double exp(x) /* wrapper exp */
double x;
#endif
{
#ifdef _IEEE_LIBM
return __ieee754_exp(x);
#else
double z;
z = __ieee754_exp(x);
if(_LIB_VERSION == _IEEE_) return z;
if(finite(x)) {
if(x>o_threshold)
return __kernel_standard(x,x,6); /* exp overflow */
else if(x<u_threshold)
return __kernel_standard(x,x,7); /* exp underflow */
}
return z;
#endif
}
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